


To Blow A Gasket

by Mendax_Mirabilis



Category: Harry Potter - J. K. Rowling
Genre: Explosions, Gen, Inferi, Muggle Technology, Muggles, Plans, Regulus Black Lives, Regulus Black-centric
Language: English
Status: Completed
Published: 2020-05-01
Updated: 2020-05-01
Packaged: 2021-03-02 00:54:08
Rating: General Audiences
Warnings: Creator Chose Not To Use Archive Warnings
Chapters: 1
Words: 3,329
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/23566384
Author URL: https://archiveofourown.org/users/Mendax_Mirabilis/pseuds/Mendax_Mirabilis
Summary: Regulus has been planning his attempt to steal the Dark Lord's Horcrux for weeks now. This involves a lot of spying, annotating and blowing things up. He knew Muggles were smart - he blames Sirius' motorbike for that unwelcome revelation, but he never knew how usefully destructive their inventions were until he started planning this heist.
Relationships: Regulus Black & Kreacher, Regulus Black & Sirius Black
Comments: 30
Kudos: 232
Collections: Regulus Black Fest 2020





	To Blow A Gasket

**Author's Note:**

  * For [Ladybird_Sparrow](https://archiveofourown.org/users/Ladybird_Sparrow/gifts).



Regulus crouched, absent-mindedly twirled his wand and stared fixedly at the fissure in the cliff. This wasn’t the first time he’d been here - nor did he think it would be the last. After all, the churning waves and chalky rock could easily become his grave and tombstone, like they almost became Kreacher’s final resting place.

It made him sick. 

The fading rays of the dying sun tainted the ocean to a dangerous red (that of the blood he’d spilled in blind faith and forced ignorance and-). 

Soon it would be too dark for him to accomplish what he’d set out to do and his time would have been frittered in fruitless contemplation. He had five hours to sit on a rock in the sea trying to scope out a dangerous place that possibly held a piece of Vol - the Dark Lord’s soul, and he’d wasted it wallowing in his regrets. 

He had far too many of those.

He cast one last glance at the cliff, straightened up and disapparated back to Grimmauld Place. It felt like he’d plunged into the water instead.

********************************************************************

Avoiding both Kreacher and his mother, he slipped quietly into his room and slumped against his closed door. 

If any of his friendly relatives came in they’d most likely see the room of a diligent, dutiful yet an ever so soft son. 

Sirius would probably call it a shrine made by a spineless puppet for a homicidal, elitist megalomaniac, but Sirius hadn’t entered this room in years and his opinion would therefore be ignored.

However, it was honestly the impression Regulus was hoping to exact from any unwelcome trespassers (family, blood-traitors, they all seemed the same nowadays -).

He pointed his wand at the newspaper clippings that adorned the wall, cataloguing Voldemort’s swift rise to power, and muttered, “Transverto.”

Immediately, the ink leached off the papers, print disappearing sliding to the edges to be replaced by cramped notes in his messiest cursive. The largest moving photograph that showed a twisting Dark Mark towering over an annihilated building, transformed into a still image of the same cliff fissure he’d been watching. An image captured by a Muggle Polaroid camera and annotated in dripping green ink. Next to it was a word-for-word account coaxed from Kreacher after the elf had been well enough to talk about his ordeal three weeks earlier.  
He had nothing to add to it tonight, but the sight of his work eased his turbulent feelings, guilt and sentimentality spilling all over the place.

He walked over to his bed and unscrewed the hollow bedpost closest to the door. It contained the camera, a counterfeit key to his brother’s motorbike (illegally duplicated) and a reconstruction of the Locket of Slytherin transfigured from a pendant he’d snatched from Hogwarts’ Room of Requirement - all wrapped under several nasty jinxes and curses that would affect him, of course.

Taking out the locket, he carefully replaced the other items and held it carefully in his curled fist. He’d placed a note inside in case he needed to replace the item he suspected to be a Horcrux in the cave, but his plan made it extremely likely that it wouldn’t be required. 

Still, better to be safe than sorry, he thought, fumbling with the door of his wardrobe with one hand and resealing his bedpost with a wave of the other. He dragged out his old school trunk, recently repurposed with an Undetectable Extension Charm (inspired by eyewitness accounts of Newt Scamander in the family library). He’d filled it up with contraband that would get him lynched by his immediate family - especially Bellatrix - if they saw it. Thankfully, no-one paid attention to the trunk of a child barely out of school.

It was the perfect hiding place for the sequestered items of a potentially suicidal plan. A plan that needed to be set into motion right about now. 

“Kreacher,” he whispered, clenching his fist around the worn leather trunk handle and only relaxing once the House-Elf apparated into his room and there was no sign of his Mother’s characteristic shrieking. She was often inconsolable in her ageing madness and any sense of familial duty he’d retained had shrivelled up and died after her banshee wailing. Still, she could be unnaturally perceptive at the most inopportune moments and it was important to ensure she had no idea of his evening plans.

Kreacher was tenser than usual, eyes darting around the room. 

“Master Regulus,” he said, wringing his hands, head bowed. “I is thinking this is a very bad idea.”

“I know, Kreacher,” replied Regulus with a crooked smile. “But I promise everything will be alright. Please, trust me.”

“Of course! Kreacher trusts Master Regulus very much, but he does not want to be losing him. Please be careful.” the elf responded, not a drop of hesitation in his tone.

“I’ll try my best,” shrugged Regulus wryly. “Let’s go."

They both disapparated with a sharp crack.

**********************************************

After retrieving a roll of what Muggles called duct tape (a waterproof variety) from the trunk and sealing it, Regulus, with Kreacher’s help, taped his wand to his right hand. Muggles really did make the most surprisingly useful things. It was better than dropping his wand in the ocean while trying to take the trunk with him, anyway.

Slipping the roll of tape into his robes, he heaved the trunk into the water and pointed his wand at it to ensure it remained still. In the moonlight, both the bobbing motions of the case and the raid bobbing of Kreacher’s throat were equally visible. The elf looked terrified, clutching a Muggle torch in one hand and a homemade wooden paddle in the other. Regulus honestly couldn’t blame him. It probably brought back memories.

On the contrary, he was feeling a creeping tendril of reckless adrenaline he hadn’t felt since before Sirius had left, when he snuck out for a ride on that treacherously beautiful motorbike with his brother despite his misgivings and cowardly fears.

It tasted warm, like hope. For the first time, he had a plan and his instincts told him he was doing the right thing. He motioned Kreacher onto the trunk and muttered a spell that kept the floating object close to him. Then he stowed his wand, took a deep breath and dived. 

The numbing cold of the water curled around his bones as he hauled himself through the water while concentrating on maintaining the spell. His right hand was still curled tightly around the wand in case the tape failed him and so his journey through the water was a clumsy one. Kreacher navigated himself with more grace, paddling to make sure the case didn’t scrape any rocks while following Regulus’ errant path.

Time stretched as they swam into the forbidding passageway, devouring minutes and spitting out hours, or so it seemed. Once they climbed up the steps and finally reached the cave, he performed a quick drying charm on both of them, but it didn’t really erase the numbness in his bones or the anticipation in his veins. The relief was profound, though.

Step one - complete.

He’d planned this next, moment countless times that it even plagued his dreams. He’d considered dynamite at first, not trusting his ward-breaking or other magical abilities to cut through such an inherently evil place, especially not through wards that demanded a blood sacrifice. But simple observation of the chalky limestone told him that it would probably bring the entire cliff down on their heads. The doubts over its structural integrity had ruled out other explosives as well, he remembered as he freed his wand hand from soggy adhesives.

He wasn’t ready to give blood - it could probably be traced and might even trigger a few dark curses. Instead, he flipped open his case and levitated out a large square of gelignite he’d nicked from some unknown Muggle dealer. It was the easiest explosive to get his hands on that wouldn’t explode without a detonator. Perfect for the job.

Kreacher had stopped shaking - thank goodness. Things going to plan had evidently bolstered him a little, and the elf pressed his fingers to where his blood had previously been spilled, before jerking sharply sideways. He then drew out a stick of chalk from the trunk and marked a sloppy X on the wall before stepping back.

Regulus slammed the gelignite towards the spot with a vicious flick of his wand and it flattened, molding itself into the cave wall. He then grabbed Kreacher, who was floating the closed trunk and pulled back down the steps of the passageway they’d come from, and sent a precise Incendio at the explosive, before ducking down rapidly. 

The resulting blast nearly knocked him back into the water as searing heat scorched over their heads. It was only his tight grip on Kreacher’s hand that kept him from falling, and quickly levitating the trunk once more as it slipped from Kreacher’s magical hold.

Cautiously they clambered up, coughing amidst the smoke still permeating the air. A gaping chasm greeted them.

He hadn’t really thought that this would work. Muggle technology against the Dark Lord’s blood wards seemed like a suicidal idea and he was waiting for some unforeseen, horrible consequences to occur. He’d prepared a delivery in case they didn’t survive the ordeal, but the diagnostic charms he tentatively performed seemed to suggest that the crazy plan had succeeded. Vol- Voldemort really did underestimate how cleverly destructive Muggle technology could be.

Then again, Regulus had joined him, simply because he feared what the technology could do once he’d discovered it. Despite his awe, the threats of Muggle wars and the dangers ‘that filth’ presented suddenly seemed more real. Added to Sirius’ departure and his parents’ displeasure, he’d ignored his own instincts and taken the Dark Mark. He’d regretted it every moment since then.

*******  
It took a while to stop wallowing in selfish pity. He’d spent a while stewing in the bitter memories of his last brotherly encounter, before the disownment.  
He’d stumbled across Sirius trying to smuggle his motorbike into his room. His brother must’ve hit the shrunken item on some stray ward or the other along the corridor and it had enlarged rather noisily, falling on top of him and flattening him. In a rare show of kindness, because he avoided Sirius as much as Sirius avoided him, Regulus cast a muffling charm and levitated the bike off of his brother. 

Sirius had scrambled for his wand and regarded him warily, but ultimately accepted his gesture and they’d both wrestled it into Sirius’ room. Unfortunately, Sirius had informed him reluctantly, the bike had blown a gasket. A few snide comments later, and a quiet inquiry about how it could move, and Sirius had described the working of its engine till dawn. 

Regulus had been enthralled. He'd never suspected that Muggles could create inventions that seemed more magical and complicated than magic itself, and he'd forgotten himself in his childish rapture.

Sirius had smirked at him - a rare occurrence - and said, "Pretty cool, huh?”

That's when everything fell apart. He'd felt a rising surge of anger and snapped out some rude comment. The rest of their fight passed in a blur and he couldn't remember much of that night except the embarrassing years that stained his bedsheets that night.

When he'd woken up, his brother was gone.

He'd been spiralling for the next two years, irrational and petty at school, and stone-cold at home. He listened to Bella, and Mother's ramblings on how Muggles had nearly wiped out both Wizardkind and themselves because they were stupid but scheming, weak yet dangerous.

The hypocrisy burned, but he paid it no mind.

He'd taken the Dark Mark despite his misgivings, fueled by spite and the desire to hurt someone, be it Sirius or himself. He convinced himself that he was protecting the world from the dangers of the Muggles, who made wondrous items like motorbikes that sped along roads. He was the only one who'd ended up bleeding, though, since his flimsy lies couldn't shield him from the truth.

Discovering the room of requirement in his sixth year was the greatest blessing of his school career. Whenever he stumbled into it, it would be stocked with Muggle textbooks on mysterious subjects like physics and philosophy, wartime magazines and instruction manuals. He'd blown up more than a few shelves mixing chemicals and had one day even walked into a shooting range and a variety of firearms. 

Soon his Muggle haven became a place he'd study non-magical weapons - in secret, of course.

No one ever suspected - they all assumed he was practicing the Dark Arts or something. Being able to keep his secrets tucked away gave him some strength and resolve for the first time, and he decided to play along until he could bring the bloody Dark Lord down.

********†****

Regulus and Kreacher tripped through the doorway, catching them on uneven rubble and leaning heavily on the walls of the cavern they found themselves in. Regulus thought they could take a minute to catch their breath and pray that things would continue to go to plan. 

Stage 3: get to the Horcrux basin.

Kreacher rooted through the contents of the case and pulled out a large flamethrower. Regulus had modified it, shrinking the gas cylinder-filled backpack portion and applying a light weight-reducing charm to the contraption to make it easier for the House-Elf to slide onto his back. Regulus then applied fire-protection spells on both of them and retrieved two large cans of gasoline from the bottom of the trunk (complete with the same weight-reducing charms).

They hurriedly clambered into the small boat, which seemed to be the easiest way to get across the Inferi-infested lake, levitating in their extra cargo. The journey wasn’t pleasant.

They were tense, with Kreacher perched on the vertical chest, pointing the nozzle of the flamethrower at the water with his jaw clenched. As they moved closer to the basin, Regulus poked a hole in the bottom of one gasoline cylinder with his wand and maneuvered it so that a steady stream of the petrol floated behind them, masking the corpses underneath.

They disembarked just as cautiously, ensuring that they didn’t touch any liquid. Regulus rounded the tiny island with the gasoline, evenly spreading it out around the island in a thick gloopy ring. The empty cans were smoothly transfigured into a makeshift barricade, plastered to the ground, with a single fluid wand movement perfected by practice. There was even a Galleon-sized hole for Kreacher to aim the flamethrower nozzle through.

He’d used a lot of magic already, and his ears still rung from the impromptu explosion. He could feel the fatigue setting in, but he made his way to the raised pedestal. 

He ran his hands over the carved pedestal, feeling where the basin joined the pillar. He plunged his free hand into the sticky liquid inside and felt the barrier that stopped him from touching it. 

He was taking a gamble with this next bit, a bit larger than all the others he’d made today. He hoped beyond hope that this one would pay off as well. He really didn’t want to drink the damned potion.  
Time for his last Muggle invention to come into play. He stowed his wand and grabbed the cordless drill he’d bought from a young, beefy Muggle from some company named Grummys - or Grummings - or something. It was an expensive model, imported from Japan or somewhere else suitably distant, and assuredly of very high quality, and the man, named Dursley, was extremely pleased to sell it to a posh, young man from a rich Muggle family who was willing to pay a hefty sum immediately. With his haughty attitude and a clean Muggle suit transfigured using an illustration as a reference, he’d pulled off the disguise, pretending to have a whimsical interest in DIY construction as a reasonable excuse. 

Regulus knelt by the basin and turned on the drill. He felt it tremble in his hand and stiffened as he tried to hold it steady. He laced it vertically against the bottom of the basin, near the join, and drove it through the stone. Several large cracks started to run throughout the structure. Flecks of debris flew away from the instrument, digging scratches into his shaking hands, but Kreacher kept a close eye on his progress, deflecting the flying detritus with one hand and positioning the flamethrower in the other. 

This was the part of his plan where the Inferi were most likely to attack them. 

Soon a small trickle of the ominous green potion splattered onto the ground. Regulus breathed a sigh of relief. It seemed that the Dark Lord hadn’t warded it from attacks from below, which worked out nicely in his favour. He drilled more holes around a fist-shaped indent, large enough to potentially put his hand through. A large steaming puddle had formed by his knees, but the basin seemed to be continuously refilling itself and the onslaught caused the whole thing to crumble to the ground.

That was when he heard a splash. 

He heaved a breath, dropped the drill and scrabbled through the soaking wreckage, searching desperately for the locket. It seemed, as he’d suspected, that the inferii were the greatest line of defence. If anything happened to the basin or potion, they would wake.

Kreacher released the flames and the smell of burning rotten flesh filled the air. He ducked down even more as the heat parched his throat and his hands finally wrapped bloody fingers around a glinting golden chain.  
Kreacher fumbled with the backpack and threw it over the barrier they’d made. The Inferi burned, caught in the throes of burning gasoline.

Regulus croaked, “Get us out of here, now!”, and his angle brushed the still open trunk. Kreacher grabbed his arm, eyes watering from the smoke and they apparated out.

***********************

Regulus sprawled on his bed, dipping his fingers in Dittany. Over by the foot of the bed, Kreacher was spreading the same on his cuts and bruises.

Walburga slept on.

They’d spent some time hysterically laughing and sobbing, though after a Muffling Charm was cast, and Regulus still couldn’t believe that they’d survived, especially by just using Muggle inventions.

Now, they lay in a post-adrenaline peaceful haze, lingering in the warm glow of triumph. They’d dealt a blow to the Dark Lord that the madman wasn’t even aware of yet. 

“Muggles really are amazing,” Regulus murmured, glancing half-lidded at the locket that lay on his desk.

Kreacher made a soft sound of agreement and dabbed some Dittany on his nose.

Regulus smiled -a full-blown grin- for the first time in years.

****************************

Professor Dumbledore was mildly surprised when an unmarked, seemingly Muggle package was dropped on his desk by a tawny owl. He cast a few diagnostic charms while he wracked his brains for any parcels he had due.

When was the last time he’d received Muggle post by an owl, anyway? Was it during his last order of Sherbert Lemon Drops..?

Ah, he was getting distracted, and the delivery didn’t seem to be cursed, so he tapped it with his wand to unwrap it.

Dumbledore had to blink in astonishment. Wrapped securely in what he was sure Muggles called Bubbly Wrap, was a small vial containing an unlabelled, silvery memory, and what seemed to be the coordinates of a specific location in the moors of Devon.

What an unusual delivery! He summoned his Pensieve and poured the contents in before plunging his head into the unknown memory with Gryffindor recklessness.  
After he resurfaced the Professor was quite pale and consumed a Lemon Drop to soothe his nerves. He also mentally added a letter to Regulus Black onto his to-do list as he considered the location where he was sure a House-Elf was waiting with a piece of Voldemort's soul.

This was a sizable lead indeed.

Maybe he should send some sweets along with that letter?

**Author's Note:**

> So the prompt I claimed was No. 42.
> 
> "Before Sirius ran away, he taught Regulus about motorcycles. And Reggie had learn to love the ingenuity of muggles. At the cave, he brought bombs / dynamite / etc....and lived the ordeal."
> 
> I have to say... this was an amazing prompt to write. I'm not that good at this writing lark rn and a found out abt the fest quite late so it took me a while, but thank you very much to RAB Fest moderators for their understanding!!
> 
> And @Ladybird_Sparrow, I hope you like it!!


End file.
